1. Field of the Invention
This invention relates to a novel antibiotic Plusbacin. In particular, it relates to a compound having a antibacterial activity and produced by cultivating a microorganism which belongs to the genus Pseudomonas and produces Plusbacin.
The novel compound of the present invention is represented by the formula: ##STR2## wherein X is L-HyPro or L-Pro, R is --CH.sub.3 or --CH(CH.sub.3).sub.2, and n is an integer from 9 to 12, or its salt.
A compound of the above formula has been designated as "Plusbacin".
2. Prior Art
As a result of recent frequent use of antibiotics, the generation of bacteria having multiple drug resistance, especially methicillin-resistant bacteria, has become serious clinical problems. The methicillin-resistant bacteria are resistant not only to methicillin but also to many other antibiotics including aminoglycosides, tetracyclines, cephems, penicillins, carbapenems, and macrolides. Therefore, there has been a strong demand for a compound having an excellent antibacterial activity against methicillin-resistant bacteria.
As an antibiotic having lipopeptide structure like the compound of this invention, there may be exemplified Daptomycin (JP Unexamd. Pat. Publn. No. 92353/1980). However, Daptomycin is structurally different from the compound of this invention.